One way a wellbore can be drilled is to use a downhole motor supported by coiled tubing. A drill bit is powered by the downhole motor and flow through the coiled tubing operates the motor. Part of the bottom hole assembly includes known tools to steer the bit so that the well is drilled with the desired orientation. The communication between the bottom hole assembly (BHA) and the surface takes place through an electric line inside the coiled tubing. After the well was drilled to the target depth, the BHA was removed with reeling in the coiled tubing and a separate coil of coiled tubing without an electric line was connected to a liner to be run in to hole bottom and then cemented.
The reason that two separate coils were required was that the coil used for drilling had the electric line in it and when it came time to displace cement that had to go through the coiled tubing a wiper plug that was typically used for cement displacement could not go down the coiled tubing because the electric line was in it. To get around this problem in the past, a separate coiled tubing reel was kept at the surface of the well so that at the conclusion of the drilling operation the reel of coiled tubing without the electric line could be deployed along with a liner running tool so that the liner could be delivered to hole bottom. Once on bottom the liner was released but remained in a sealed relation to the running tool so that cement could be delivered in the required volume into the liner. The liner had a cementing shoe on bottom. Typically, the liner had a wiper plug on top with a passage through it through which the cement was delivered. After delivery of a measured volume of cement a dart would be launched to land in the wiper plug and pressure was built up to launch the wiper plug to land it just above the cement shoe at the liner bottom. This would push all the cement into the annular space surrounding the liner. The coiled tubing could then be released from the liner and the excess cement circulated out. The coiled tubing would then be coiled up on the reel at the surface. While this procedure got the job done it was expensive to keep two coiled tubing reels at the well site and the present invention addresses a way to get the same job done without employing the second coiled tubing assembly. It can also provide an assurance that uncontaminated cement is delivered to the annulus around the liner to be cemented and a way to remove an excess amount of barrier cement from the coiled tubing to insure its continuing functionality for other jobs. These and other aspects of the present invention will be more readily apparent to those skilled in the art from a review of the detailed description of the preferred embodiment and the associated drawings while recognizing that the full scope of the invention is to be determined by the literal and equivalent scope of the attached claims.